Interchangeable orthopedic blade

ABSTRACT

An interchangeable orthopedic blade including an internal portion and an external portion. The internal portion more accurately places the interchangeable orthopedic blade in, without excessive damage to, a bone when repairing a fracture in the bone and ultimately provide absolute stable fixation by the interchangeable orthopedic blade holding the fracture in its anatomic position and resisting applied forces while healing, to thereby provide a stable anatomic restoration and eliminate a need for revision surgery due to failure of fixation or malunion. The internal portion is received in the external portion and rotates relative to the external portion, but has the external portion move non-rotatably axially with the internal portion into the bone as the internal portion threads. In a first preferred embodiment, the internal portion is a screw with an externally threaded head. In a second preferred embodiment, the internal portion is an externally threaded set screw.

1. CROSS-REFERENCE TO RELATED APPLICATION

The instant non-provisional patent application is a Continuation-In-Partapplication of non-provisional patent application Ser. No. 13/550,955,filed on Jul. 17 2012, entitled INTERCHANGEABLE ORTHOPEDIC BLADE, andwhich claims the benefit of provisional patent application No.61/689,402, filed on Jun. 4, 2012, and entitled INTERCHANGEABLEORTHOPEDIC BLADE.

2. BACKGROUND OF THE INVENTION

A. Field of the invention

The embodiments of the present invention relate to an orthopedic blade,and more particularly, the embodiments of the present invention relateto an interchangeable orthopedic blade for more accurately placing in,without excessive damage to, a bone when repairing a fracture in thebone by cooperating with an interchangeable orthopedic plate, so as toprovide absolute stable fixation by holding the fracture in its anatomicposition and resist applied forces while healing, to thereby provide astable anatomic restoration and eliminate a need for revision surgerydue to failure of fixation or malunion.

B. Description of the Prior Art

(1) General Principles of Internal Fixation.

(a) History of Fracture Treatment.

Fractures have been treated with immobilization, traction, amputation,and internal fixation throughout history. Immobilization by casting,bracing, or splinting a joint above and below the fracture was used formost long bone fractures, with the exception of the femur for whichtraction was the mainstay of treatment. In the past, open fractures andballistic wounds with long bone fractures were not amenable to standardfracture care because of the associated soft tissue injury and thedifficulty in preventing sepsis. Thus, they usually resulted inamputation, especially during the US Civil War.

Although the concept of internal fixation dates back to the mid 1800s,Lister introduced open reduction and internal fixation (“ORIF”) ofpatella fractures in the 1860s. Use of plates, screws, and wires wasfirst documented in the 1880s and 1890s. Early surgical fixationinitially was complicated by many obstacles, such as infection, poorlyconceived implants and techniques, metal allergy, and a limitedunderstanding of the biology and mechanics of fracture healing. Duringthe 1950s, Danis and Muller began to define the principles andtechniques of internal fixation. Over the past 40 years, advancements inbiological and mechanical science have led to contemporary fixationtheories and techniques.

(b) Introduction to Fracture Repair Biology.

Disruption of the endosteal and periosteal blood supply occurs with theinitial trauma. Maintaining adequate blood supply to the fracture siteis essential for healing. Hunter described the four classic stages ofnatural bone repair: inflammation; soft callus; hard callus; andremodeling. The inflammation stage begins soon after injury and appearsclinically as swelling, pain, erythema, and heat. Disrupted localvascular supply at the injured site creates a hematoma and prompts themigration of inflammatory cells that stimulate angiogenesis and cellproliferation. After the initial inflammatory phase, the soft callusstage begins with an infiltration of fibrous tissue and chondroblastssurrounding the fracture site. The replacement of the hematoma by thisstructural network adds stability to the fracture site.

Soft callus is then converted into rigid bone, the hard callus stage, byenchondral ossification and intramembranous bone formation. Once thefracture has united, the process of remodeling begins. Fibrous bone iseventually replaced by lamellar bone. Although this process has beencalled secondary bone union or indirect fracture repair, it is thenatural and expected way fractures heal. Fractures with less than ananatomic reduction and less rigid fixation—i.e., those with large gapsand low strain via external fixator, casting, and intramedullary (“IM”)nailing—heal with callous formation or secondary healing withprogression through several different tissue types and eventualremodeling. Anatomic reduction and absolute stabilization of a fractureby internal fixation alter the biology of fracture healing bydiminishing strain—elongation force—on the healing tissue at thefracture site. Absolute stability with no fracture gap—e.g., via ORIFusing interfragmental compression and plating—presents a low strain andresults in primary healing—cutting cone—without the production ofcallus. In this model, cutter heads of the osteons reach the fractureand cross it where bone-to-bone contact exists. This produces union byinterdigitation of these newly formed osteons bridging the gap. Thesmall gaps between fragments fill with membranous bone that remodelsinto cortical bone as long as the strain applied to these tissues doesnot cause excessive disruption and fibrous tissue develops—nonunion.This method of bone healing is known as direct bone healing or primarybone union. Essentially, the process of bone remodeling allows bone torespond to the stresses to which it is exposed.

Based on the mechanical milieu of the fracture as dictated by thesurgeon's choice of internal fixation and the fracture pattern, twopatterns of stability can result that determine the type of bone healingthat will occur. Absolute stability—i.e., no motion between fracturefragments—results in direct or primary bone healing—remodeling. Relativestability—i.e., a certain amount of fragment motion—heals with secondaryor indirect bone union.

(c) Pins and Wires.

Kirschner wires—K-wires, 0.6-3.0 mm—and Steinmann pins—3-6 mm—have avariety of uses from skeletal traction to provisional and definitivefracture fixation. Resistance to bending with wires is minimal so theyare usually supplemented with other stabilization methods when used forfracture fixation, but most commonly, wires are utilized as provisionalfixation prior to definitive fixation with a stronger device. Skeletaltraction with K-wires is possible with the use of a K-wire tensionerthat with application stiffens the wire and allows it to resist bendingload.

K-wires and Steinmann pins can provide provisional fixation forreconstruction of fractures, while incurring minimal bone and softtissue damage and leaving room for additional hardware placement.Planning pin placement is important to avoid the eventual permanentfixation devices, and if possible, pins should be placed parallel toscrews used for fracture compression. Depending on the diameter, pinsmay also be used as guidewires for cannulated screw fixation.

Permanent fixation options include fractures in which loading is minimalor protected with other stabilization devices, such as externalfixators, plates, and braces. Pin or wire fixation is often used forfractures of the phalanges, metacarpals, metatarsals, proximal humeri,and wrists. K-wires commonly supplement tension-band wire constructs atolecranon, patella, and medial malleolus fractures.

The K-wires can be fully threaded or nonthreaded, and have eitherdiamond or trocar points that are simplistic in design and have limitedability to cut hard bone—a process that can lead to overheating. Forthis reason, they should be inserted slowly when power equipment is usedto avoid thermal necrosis. Image intensifiers are often used for optimalpositioning of the fixation, especially with percutaneous insertioncombined with closed reduction techniques. The pins may have points atboth ends, facilitating antegrade-retrograde fixation techniques. Theyare, however, a potential hazard and should be used with caution.

Steinmann pins are larger, may be threaded or unthreaded, and arecurrently used primarily for long bone traction in conjunction with aBailer traction stirrup. Early techniques of fracture treatmentconsisting of pins for skeletal traction and incorporation into a castwere fraught with pin infections, loosening, and loss of reduction. Thistechnique has been replaced with more advanced external fixationdevices, internal fixation methods, and minimally invasive plating andIM devices.

Guidewires for cannulated screws are employed at times for definitivefixation as they are terminally threaded allowing for fixation on theopposite cortex. An example of this would be the closed reduction andpercutaneous pinning technique for proximal humeral fractures.

(d) Screws.

Bone screws are a basic part of modern internal fixation. They can beused independently or in combination with particular types of implants.The common design of a screw consists of a tip, shaft, thread, and head,as shown in FIGS. 1-3. A round screw tip requires pretapping, whereas afluted screw tip is self-tapping. The screw shaft is located between thehead and the threaded portion of the screw. The screw thread is definedby its major or outside thread diameter and minor or root shaftdiameters, pitch, lead, and number of threads. The distance betweenadjacent threads is the pitch.

The lead is the distance a screw advances with a complete turn. Lead isthe same as pitch if the screw is single threaded, and lead is twice thepitch if the screw is double threaded—faster screw insertion. The rootdiameter determines the screw's resistance to breakage—tensile strength.Screws are referred to by their outer thread diameters, bone type forintended use—cortical or cancellous determined by pitch and major/minordiameters—and proportion of thread—partially or fully threaded.

Screw pullout strength can be affected by several factors. Bonecomposition density—is the primary determinant of screw fixation. Thetotal surface area of thread contact to bone—root area—is another factorin pullout resistance. Pretapping the screw hole theoretically reducesmicrofracture at the thread-bone interface, but requires an extra stepfor insertion. Self-tapping screws have been shown to have no clinicaldifference from pretapped screws for fracture or plate fixation,eliminate the tapping step, and are now the industry standard. Thefluted portion of the screw tip has less thread contact with the bone soslight protrusion at the opposite cortex is recommended.

Pitch—the distance between adjacent threads—affects purchase strength inbone. Increasing the pitch increases bone material between the threads,but decreases the number of threads per unit of distance.

The industry standard for the screw head is a hexagonal recess thatprovides a large contact surface between the screw head and screwdriverand allows for optimal transmission of torque, as shown in FIG. 3. Across-type screw head is used on some screws in the 2.0 and smallerscrew—minifragment—sets. The star design or TORX head found in industryhas been adapted to the screw heads for the Association for the Study ofInternal Fixation (“AO/ASIF”) locking plates, and has been shown to besuperior for torque and resistance to stripping.

Several forces are involved with screw insertion and tightening. Torqueis applied through the screwdriver to the screw head in a clockwiserotation to advance the screw in the predrilled path—or in the case of acannulated screw—over a guidewire. This advancement produces acircumferential force along the thread. For cortical screws, the drilldiameter is slightly larger than the root—shaft—diameter of the screw.Axial tension is created with impingement of the screw head on thecortex or plate generating tension through the screw. To optimize theseforces, screws should ideally be inserted at 80% of the torque needed tocause them to strip. An estimated 2500-3000 newtons of axial compressionforce can be applied to the average screw. Over time, the amount ofcompressive force decreases slowly as the living bone remodels to thestress. The fracture healing time, however, is usually shorter than thetime it takes for substantial loss of compression and fixation.

The two basic types of screws available for the variability of bonedensity are cortical and cancellous screws. Cortical screws are designedfor compact diaphyseal bone, whereas cancellous screws are designed forthe more trabecular metaphyseal bone. Cortical screws have a smallermajor—thread—diameter, decreased pitch, and a shallower thread thancancellous screws. Standard nonlocking cortical screw diameter choicesinclude 1.5, 2.0, 2.7, 3.5, and 4.5 mm.

Cancellous screws typically have a larger major—thread—diameter andpitch and a greater difference between major and minor—shaft—diametersin comparison to cortical screws providing more surface area for bonepurchase. These screws are intended for use in metaphyseal fixationwhere bone is softer. Cancellous screws are available in sizes 4.0 and6.5 mm, and cannulated sizes vary from 4.0-7.5 mm.

Tapping is not usually necessary in metaphyseal bone, as cancellous boneis porous relative to compact diaphyseal bone and usually requires onlythe initial pilot hole or cannulated screw guidewire. With subsequentscrew insertion, there is compression of the bone along the path of thethreads, which increases the local bone density in contact with thethread, thereby potentially increasing screw purchase. Tapping may beconsidered in strong metaphyseal bone to avoid stripping if advancementof the screw is difficult.

Positional or neutralization screws are to attach an implant, such as aplate, to bone by compression between the plate and bone, as shown inFIG. 4. This function is modified when the screw is used to lag across afracture through the plate or when used for fracture compression, aswith a dynamic compression screw. For a positional screw, the pilot holeis drilled with the appropriate-size bit—shaft diameter—for the screw tobe inserted—e.g., a 3.2-mm drill bit for a 4.5-mm screw—using acentering guide for the plate hole. A depth gauge is used to determineappropriate screw length, and the thread cut is then made with anappropriate tap or without a tap when self-tapping screws are used orscrews are placed in metaphyseal bone.

Interfragmentary lag screws provide compression across two bone surfacesusing the lag technique. A lag screw is a form of static compression,and is applicable to intra-articular fractures to maintain reduction anddiaphyseal fractures for stability and alignment. Ideally, lag screwfixation produces maximum interfragmentary compression when the screw isplaced perpendicular to the fracture line, as shown in FIGS. 5-7. Mostlag fixation techniques require additional stabilization to neutralizethe axial bending and rotational forces applied to the bone duringfunctional postoperative care. This is provided by a neutralization orbuttress plate or external fixation.

If lag screws are to be used without neutralization plate fixation,especially in long spiral fractures>2 times the diameter of the involvedbone—the ideal inclination of the screw is halfway between theperpendiculars to the fracture plane and to the long axis of the bone.Placing the screw perpendicular to the long axis of the bone can also beconsidered because longitudinal or shear compression may cause the screwor screws to tighten. Interfragmentary screw fixation alone may beappropriate for avulsion injuries in which shear forces generatemetaphyseal and epiphyseal intra-articular fractures provided bonequality is good.

A fully threaded screw can serve as a lag screw with the near cortexover-drilled to the size of the screw's major—thread—diameter, 4.5 mm inthe example, as shown in FIGS. 8 and 9. Once the near cortex is drilled,which provides a gliding hole, a drill sleeve with the outer diameter ofthe drill bit—4.5 mm—is inserted into the hole, and the standard drillbit—3.2 mm shaft diameter—is used to drill the far cortex. As the screwthreads grasp the distal cortex, compressive forces are generatedthrough the axis of the screw to the screw head causing the fracturefragments to be compressed. This same mechanical effect can be generatedby a partially threaded screw, with all threads entirely within theopposite bony fragment.

Cannulated screws are now provided by most trauma manufactures in sizesfrom minifragment to 7.5 mm usually with a cancellous thread, butcortical patterns are also available as they are more commonly used inperiarticular/metaphyseal bone. The guidewire is usually placed underfluoroscopic control, and allows for initial provisional fixation.

Cannulated screws allow for a percutaneous technique, such as is usedwith hip pinning, or may be used with limited open reduction techniquesand can help minimize soft tissue dissection and periosteal stripping.Most designs are now self-drilling and self-tapping, but some mayrequire predrilling over the guidewire with dense bone. The guidewiresare usually terminally threaded—although nonthreaded are available—andwhen drilling over the wire, it is recommended not to drill over thethreaded portion because the guidewire may be inadvertently removedalong with removal of the drill bit. This could result in difficultyrelocating the drill hole through soft tissue or loss of provisionalfixation.

The pullout strength of cannulated 7-mm cancellous screws versus 7-mmnoncannulated screws and 3.5-mm cannulated and noncannulated screws hasbeen tested in two studies, and no significant difference was notedregarding pullout strength. These studies, however, are specific tothese screw designs and similar fixation properties cannot necessarilybe applied to other screw designs and sizes. It should also beconsidered that the relative costs of cannulated screws are often tentimes that of similar-sized noncannulated screws. Therefore,noncannulated screws should be used when technically feasible.

Self-tapping screws have the advantage of eliminating a step duringscrew insertion, thereby decreasing operative time. The fluted design ofthe screw cuts a sharp path in the predrilled hole eliminating the needfor tapping. Baumgart and associates showed that insertion torque andpullout strength were comparable for tapped and self-tapping screws.Only if the cutting tip did not protrude through the second cortex didthey find a reduction of pullout strength of approximately 10%.

Schatzker and associates went on to prove that self-tapping screwsinserted at 80% of thread-stripping torque, and then removed andreinserted twelve times did not lose any significant holding power. Wheninserting a self-tapping screw as a lag screw, care should be taken withtechnique to avoid missing the opposite cortex as these screws are oftenat an angle to the diaphyseal shaft or there may be difficulties withadvancing the screw while also tapping, especially with hard corticalbone. It is not unreasonable to consider tapping this opposite cortexfirst to help with alignment and advancement of the lag screw.

Locked screws are incorporated in more recent plate designs, and may beinserted as unicortical or bi-cortical screws depending on the type ofplate and fracture. These screws—with reduced pitch—produce minimalaxial force—if any—and provide biomechanical fixation by locking thescrew head into the plate with a tapered thread perpendicular to theplate. Some newer designs allow for some variable angulation of thelocking screws. The system acts generally like an internal-externalfixator, as shown in FIGS. 10 and 11. These systems are discussedfurther in Plates below.

(e) Plate Types.

Plates are provided in various sizes and shapes for different bones andlocations. Dynamic compression plates (“DCPs”) are available in 3.5 mmand 4.5 mm sizes. The screw holes in a DCP are shaped with an angle ofinclination on one side away from the center of the plate. Whentightened, the screw head slides down the inclination causing movementof the bone fragment relative to the plate, as shown in FIG. 12. As onebone fragment approaches the other at the fracture, compression occurs.The shape of the holes in the plate allow for 25° of inclination in thelongitudinal plane and 7° inclination in the transverse plane for screwinsertion.

The dynamic compression principle requires that the holes of the platebe shaped like an inclined and transverse cylinder. Like a ball, thescrew head slides down the inclined cylinder. Because the screw head isfixed to the bone via the shaft, it can only move vertically relative tothe bone. The horizontal movement of the head as it impacts the angledside of the hole, results in movement of the bone fragment relative tothe plate, and leads to compression of the fracture.

Limited-contact DCPs (“LC-DCPs”) were designed to limit possible stressshielding and vascular compromise by decreasing plate-to-bone contact by50%, as shown in FIG. 13.

Theoretically, this leads to improved cortical perfusion with increasedpreservation of the periosteal vascular network, and reducesosteoporosis under the plate. The regular DCP has an area of decreasedstiffness located at the plate holes, and with bending, has a tendencyto bend at the holes with a segmented pattern, whereas the LC-DCP—with adifferent geometric design incorporating the holes and plateundersurface—allows for gentle bending distributed throughout the plate,as shown in FIGS. 14A and 14B.

Finally, the LC-DCP is designed with plate hole symmetry providing theoption of dynamic compression from either side of the hole, and allowingcompression at several levels. In general, standard DCP style plateswere replaced years ago with updated designs by most manufacturers withvariations on the LC-DCPs, and in turn, these plates have been replacedby all manufacturers with plates capable of both locking and nonlockingfunctions. Some specific non-locking-style plates are still retained inuse as they function well for a variety of specific fractures, such asthe one-third tubular plate for lateral malleolar fractures and the 3.5mm recon plates for periacetabular fixation.

Techniques for the application of both the DCP and LC-DCP are the same,as shown in FIG. 15. Screws can be inserted in neutral position or acompression position depending on the desired mechanical result. The DCPuses a green guide to insert a neutral screw, which adds somecompression to the fracture owing to the 0.1-mm offset. The gold guideproduces a hole 1 mm off-center, away from the fracture, and allows for1 mm of compression at the fracture site with tightening of the screw.The LC-DCP universal drill guide allows for either neutral or eccentricplacement of screws. When creating an eccentric hole to one side oranother, the guide is slid to the end of the plate hole without applyingpressure, and the hole is drilled. By placing pressure against the bonewith the drill guide, the spring-loaded mechanism allows forcentralization of the hole for neutral screws—particularly if the screwmust be inserted at an angle to the plate.

The 3.5 one-third tubular plate is 1 mm thick and allows for limitedstability, as shown in FIG. 16. The thin design allows for easy2-dimensional contouring and is primarily used on the lateral malleolus,and on occasion, the distal ulna. The oval holes allow for limitedfracture compression with eccentric screw placement.

Improvements by all manufacturers have been made for plates used foralmost all areas of the body that require placement of a plate near ajoint and over extended areas of diaphyseal bone. The refinement ofcontour—along with screw head modification reduces hardware prominenceand increases fixation options.

The 95°-angled plates are useful in the repair of metaphyseal fracturesand reconstruction of the femur as they provide very rigid fixation, asshown in FIGS. 17A-17D. They are technically demanding, and properinsertion requires the blade to be inserted with consideration of 3dimensions—i.e., vagus/valgus angulation, anterior/posterior position,and flexion/extension rotation of plate. The screw barrel devices areconsidered somewhat easier to insert because the flexion/extension ofthe plate is correctable after insertion of the screw.

Reconstruction plates are thicker than one-third tubular plates, butthey are not quite as thick as DCPs, as shown in FIGS. 18A and 18B.Designed with deep notches between the holes, they can be contoured inthree planes to fit complex surfaces—e.g., around the pelvis andacetabulum. Reconstruction plates are provided in straight and slightlythicker and stiffer precurved lengths. As with tubular plates, they haveoval screw holes allowing potential for limited compression.

Cable plates incorporate a large fragment plate with cerclage wires tobe used with a tensioning device. These are used primarily with femoralfractures surrounding or adjacent to prosthetics—femoral hip or kneeimplants. Cortical allograft struts are often incorporated forosteoporotic bone.

(f) Plate Functions.

Standard plate fixation requires exposure of the fracture site, hematomaevacuation, and reduction of the fracture with possible interfragmentarylag fixation. After a fracture occurs, the periosteal blood supply isdominant, and this network of connective tissue must be preserved tooptimize healing. Excessive periosteal stripping and careless softtissue techniques can impair local blood supply and prolong healing.

Diaphyseal plate fixation associated with an anatomic reduction andinterfragmentary compression provides absolute stability. Plates areoften indicated in articular fractures to neutralize the axial forces onthe interfragmentary screws compressing cancellous bone to facilitateits healing. A fracture anatomically reduced without a gap and fixedwith absolute stable fixation will undergo primary healing.

Dead bone at the fracture site is resorbed by osteoclasts of the cuttingcones as these cells traverse the fracture site. The osteoclasts areclosely followed by ingrowth of blood vessels and mesenchymal cells andosteoblast infiltration. Stress shielding of the bone is rarely causedby the plate relieving axial load to the bone. Plate-inducedosteoporosis is caused by disruption of the local vascularity to thebone cortex secondary to an impediment of centrifugal cortical bloodflow by the plate.

Osteoporosis under a plate should be kept in mind after removal ofhardware because the bone also has the mechanical disadvantage of emptyscrew holes. This vascular-caused cancellization of the cortical bone indiaphyseal areas usually resolves within two years of plate applicationso it is safe to remove a plate at this time with the refracture ratebeing minimal. Plates applied to metaphyseal areas may have the optionof earlier removal depending on the amount of diaphyseal extension andhealing.

Bridge plating is used for comminuted unstable fractures in whichanatomic restoration and absolute stability cannot be achieved. Minimalexposure and indirect reduction techniques are used to preserve theblood supply to the fracture fragments for healing, and a plate isattached to the two main fragments spanning the area of fracture. Theplate is used to provide proper length, axial alignment, and rotation,but it is obviously limited for any load.

With more recent advances of combining minimally invasive platetechniques utilizing locking plate technology, plate devices act more asan internal fixator. This approach began in 2001 with the Less InvasiveSurgical Stabilization (“LISS”) plate that is advanced in thesubmuscular tissue through a small incision over the periosteum, butdoes not necessarily contact the bone along the length of the plate.This technique limits the disruption of periosteal blood supply that isseen in conventional plating systems as the fixation is through thelocking screws, thereby not necessitating compression to the plate forstability. The early development of this concept with the Point ContactFixator (“PC-Fix”) system in the 1990s—and then later with LISS—takesadvantage of unicortical, self-drilling, and self-tapping screws withthreaded screw heads that lock into the screw hole of the plate andminimize soft tissue disruption.

Once the LISS plate is aligned with the central shaft of the bone, screwplacement can be accomplished percutaneously with a radiolucent guideattachment to the plate. Unicortical screws are recommended for use indiaphyseal bone, with longer screws for use in the metaphyseal area,thereby functioning as a fixed-angle device.

Currently, most manufacturers offer new locking plate products. Thesedevices range from standard straight plates of all sizes with lockingand standard screws to anatomically specific plates that act asfixed-angle devices. These new plate designs incorporate improvedcontour with locking screw options for fixation offering significantadvantages over the conventional designs for certain fractures. Proximaland distal humerus, distal radius, distal femoral, andproximal—bicondylar—and distal tibial fractures are examples of injuriesthat benefit from this technology having the improved ability to hold afracture in its anatomic position and resist applied forces whilehealing. Conventional plates—that rely on friction forces against theplate from screw fixation and buttressing in metaphyseal and articularfractures—are limited in resisting applied loads versus lockingfixation.

In contrast, certain shaft fractures with stable patterns and adequateroom for fixation have proven high union rates with conventionalplating—humeral shaft, radius, and ulna shaft—and any significantdifference between the two techniques is difficult to realize withproper surgical technique. Current recommendations are to use lockingscrews in situations with limited fixation options, osteoporotic bone,or need for fixed-angle support. For example, a simple lateral plateaufracture that requires buttress fixation and with which the bone qualityis reasonable can be adequately treated with a conventional nonlockinglateral plate.

Currently, most LC-DCP small and large conventional plate sets have beenreduced as utilization of specialty plates has increased withperiarticular design and locking capability, the surgeon deciding whichscrews are locking or nonlocking depending on the fracture. As withcannulated screws, locking screws can vary in cost ranging from 8-15times the cost of a conventional screw, and therefore should be usedwhen needed based on the fracture pattern and expected loads. This costissue is lessened to some degree when taking into account the need forrevision surgery due to failure of fixation or malunion. Thus, a balanceof usage guided by conventional wisdom, common sense, and biomechanicaland outcome studies is recommended.

(g) Tension-Band Principle.

Plates and other constructs can be used to function as a tension-band ifan eccentrically loaded bone—e.g., the femur—has the device placed onthe tension-convex side of the bone. Using load-strain diagrams,Frederic Pauwels—who first described the tension-band concept—showedthat a curved tubular structure placed under an axial load had a tensionside and a compression side. With this theory, he described theapplication of internal fixation on the tension side to convert tensileforces into compressive forces at the fracture site.

With static compression applied by the implant—e.g., tensioning of wirecompression with plate—dynamic compression then develops with jointflexion as with a patella or olecranon fracture or with load as withlateral femoral plating, as shown in FIGS. 19A and 19B. With thistechnique, the internal fixation device must have the strength towithstand the tensile distraction forces created by muscles duringmotion, and the bone on the opposite side of the plate must be able towithstand the compressive forces as a medial buttress.

Wires and plates are usually quite strong under pure tension forces, butwith bending forces added fatigue can occur rapidly. If bony support iscompromised on the cortex, opposite from the tension device—e.g., fromfragmentation, osteoporosis—bending stresses can develop causing failureof fixation. Wiring techniques commonly include longitudinal K-wires forrotational and axial alignment control in the case of bonefragmentation.

Conversely, fixation on the concave side of the bone occurs in raresituations, such as with medial plating of a femur or anterior platingof the humerus. In these situations, fractures have minimal resistanceto bending stresses, and gapping can occur on the convex side resultingin failure of fixation, as shown in FIG. 20. Therefore, attempts shouldbe made to limit potential bending forces to fixation to preventfixation failure. The tension-band principle can be applied to wires,cables, sutures, plates, and external fixators as long as the basicprinciples are followed.

(2) Angled Plates.

(a) General Principles.

In 1959, the AO developed the angled plates, as shown in FIGS. 21 and22. The “U” profile was chosen for the blade portion, and a single bladeunit with a fixed angle between the blade and the plate was adopted inpreference to the two-piece variable angle devices. The advantage of thefixed angle is the increased strength and the increased corrosionresistance of the implant. The disadvantage is the increased difficultyof insertion. In the proximal femur, the blade has to be inserted in themiddle of the femoral neck and at a predetermined angle to the shaftaxis. In addition, the plate portion of the angled blade plate has to beinserted so that it will line up with the axis of the shaft at the endof the procedure. In the distal femur, the blade has to line up with thejoint axis and with the inclination of the patellofemoral joint and beinserted exactly into the middle of the anterior half of the femoralcondyles at a predetermined distance from the joint, and the plate hasto line up with the axis of the femoral shaft. Because of thesetechnical complexities, a preoperative plan—including a preoperativedrawing—is essential so that the operation can follow it step-by-step.The surgeon must also exercise great care at the time of surgery and payparticular attention to anatomic landmarks, position, and inclination ofthe implants in order to follow the preoperative plan. This usuallyensures that at the end of the procedure, everything fits and that thedesired end result is achieved.

(b) Preoperative Planning

An X-ray of the normal side is required in order to have a template onwhich to plan the procedure. For the proximal femur, the X-ray must betaken with the hip in 15°-20° internal rotation to correct forante-version. For the distal femur, accurate antero-posterior andlateral X-rays centered on the joint are necessary. The outlines of theproximal or the distal femur are drawn in, as are all the fracturelines. The fracture pattern determines the steps of the internalfixation, as well as the choice of plate. The selected plate is drawn inwith the help of the templates. The plan should include the order inwhich the different steps will be carried out, should denote thefunction of the different screws, should indicate if a gliding hole or athread hole needs to be predrilled before the reduction is carried out,and whether a bone graft is necessary. All the guide wires that arenecessary to execute the procedure must also be shown, and theirfunction and inclination carefully noted Schatzker rationale.

These working drawings are necessary before any surgical procedure isembarked upon. They are of particular importance before correctiveosteotomies because they are the only way the surgeon can checkpreoperatively the result of the osteotomy, as well as thethree-dimensional concept of the procedure.

(c) Implants and Instruments.

A number of specialized instruments have been developed that greatlyfacilitate the exact execution of the operation in accordance with thepreoperative plan. Neither an X-ray nor an image intensifier is asubstitute for a three-dimensional concept of the local anatomy, norwill they serve as a guide to the correct insertion of the guide wires.Correct insertion is based on the anatomic landmarks and on theparticular device employed for fixation. The X-ray or the imageintensifier are, however, useful to verify the definitive insertion ofthe seating chisel or of the specialized guide wire for the dynamic hipor condylar screw. An X-ray is also useful as a permanentintra-operative record of the position of the guide wires and of all theinternal devices, as well as of the position of an osteotomy if one isbeing carried out.

(d) the Angled Plates for the Proximal and Distal Femur.

Initially, as shown in FIG. 21, the AO developed the 130° plate for usein the proximal femur, and, as shown in FIG. 22, the condylar bladeplate is for use in the distal femur. With time it became evident thatthe condylar plate could also be used for the treatment of certaininter-rochanteric and subtrochanteric fractures of the proximal femur.Following further modifications and refinements, the AO has developedthe dynamic hip screw (“DHS”) and the dynamic condylar screw (“DCS”).These two have almost replaced the “U” profile angled blade plates inthe treatment of fractures, but the latter continue to be used inreconstructive surgery, such as osteotomies. The original fixed angledevices are described in detail because all the specific features,indications, and anatomic considerations apply in exactly the same wayas to the DHS and to the DCS.

The 130° angled plate has a blade with a “U” profile, as shown in FIG.21. The plate portion comes in varying lengths depending on theparticular fracture to be fixed. Thus, the four- or six-hole plates areused for most intertrochanteric fractures, and the plates—9-12 holes—forsubtrochanteric fractures.

The condylar plate has a fixed angle of 95° between its blade and plateportion, as shown in FIG. 22. The shortest plate available has fiveholes. The length to be used will vary with the fracture pattern. Theshortest blade is 50 cm, and the length of the blade chosen will dependon the size of the femur and whether the plate is being used in thedistal or proximal femur.

Numerous innovations for osteosynthetic devices have been provided inthe prior art, which will be described below in chronological order toshow advancement in the art, and which are incorporated entirely hereinby reference thereto. Even though these innovations may be suitable forthe specific individual purposes to which they address, nevertheless,they differ from the embodiments of the present invention in that theydo not teach an interchangeable orthopedic blade for more accuratelyplacing in, without excessive damage to, a bone when repairing afracture in the bone by cooperating with interchangeable orthopedicplate, so as to provide absolute stable fixation by holding the fracturein its anatomic position and resist applied forces while healing, tothereby provide a stable anatomic restoration and eliminate a need forrevision surgery due to failure of fixation or malunion.

(1) U.S. Pat. No. 4,711,232 to Fischer et al.

U.S. Pat. No. 4,711,232—issued to Fischer et al. on Dec. 8, 1987 in U.S.class 606 and subclass 67—teaches a fastener for anchoring in a bore ina bone, which has a screw with a substantially cylindrical outer surfaceformed with a helical screw thread. The screw has at its screw thread, athread diameter, and between the turns of the thread at the surface, aroot diameter smaller than the thread diameter. A synthetic-resin anchorsleeve of a resilient fitted in the bore is of an outside diametercorresponding generally to the diameter of the bore, and has an outerend formed with an outwardly open polygonal-section recess, an inner endformed with an inwardly open and transversely through-going slot, anouter end portion of an inside diameter greater than the root diameterbut smaller than the thread diameter, an inner end portion of an insidediameter smaller than the root diameter, and an external helicoidalscrew thread extending about two-thirds of the length of the sleeve fromits inner end toward its outer end.

(2) U.S. Pat. No. 5,098,434 to Serbousek.

U.S. Pat. No. 5,098,434—issued to Serbousek on Mar. 24, 1992 in U.S.class 606 and subclass 308—teaches a bone screw for joining bonefragments or for mounting a prosthetic component onto an underlyingbone. The bone screw includes a head and an elongated cylindrical shankthat is integral with, and extends from, the head. The shank includes athreaded member and a shoulder member connecting the threaded member andthe head. The shoulder member has an outer surface with a porous mediumthereon for encouraging bone ingrowth fixation. The outer diameter ofthe shoulder member is greater than the diameter of a bore of the boneinto which the screw is to be threadedly engaged. The head of the screwis provided with a coupling member engageable by a tool for selectivelyrotating the shank to advance the screw into the bone. As the bone screwis advanced toward a fully seated position, the shoulder member with theporous medium thereon engages the bone in a fitting manner that isdescribed as a “scratch fit.” Initial loosening of the bone screw due tothe viscoelastic relaxation of the bone tissue following fixation isthereby largely inhibited and long term loosening of the bone screw isalso inhibited by providing an interface onto which, or into which, bonetissue can grow to stabilize the repair site or the implanted component.

(3) U.S. Pat. No. 5,899,906 to Schenk.

U.S. Pat. No. 5,899,906—issued to Schenk on May 4, 1999 in U.S. class606 and subclass 301—teaches a threaded washer having a central bore foruse with a bone screw. The washer is threaded into a counterboreextending below the bone surface and into cancellous bone material. Theexternal washer threads are tapered. The bone screw is inserted throughthe central bore of the washer and threaded into the fragment beyond thefracture. The washer permits the bone screw head to be located beneaththe bone surface.

(4) U.S. Pat. No. 5,997,541 to Schenk.

U.S. Pat. No. 5,997,541—issued to Schenk on Dec. 7, 1999 in U.S. class606 and subclass 303—teaches a threaded washer having a central bore foruse with a bone screw. The washer is threaded into a counterboreextending below the bone surface and into cancellous bone material. Theexternal washer threads are tapered. The bone screw is inserted throughthe central bore of the washer and threaded into the fragment beyond thefracture. The washer permits the bone screw head to be located beneaththe bone surface.

(5) U.S. Pat. No. 6,048,344 to Schenk.

U.S. Pat. No. 6,048,344—issued to Schenk on Apr. 11, 2000 in U.S. class606 and subclass 916—teaches a threaded washer having a central bore foruse with a bone screw. The washer is threaded into a counterboreextending below the bone surface and into cancellous bone material. Theexternal washer threads are tapered. The bone screw is inserted throughthe central bore of the washer and threaded into the fragment beyond thefracture. The washer permits the bone screw head to be located beneaththe bone surface.

(6) United States Patent Application Publication Number 2010/0331895 toLinke.

United States Patent Application Publication Number2010/0331895—published to Linke on Dec. 30, 2010 in U.S. class 606 andsubclass 304—teaches an osteosynthetic device for the fixation of a boneor bone fragments, which has a longitudinal axis, and includes a bonescrew with a shaft bearing a thread, a front end, and a rear end. Thethread has a maximum outer diameter, and a wing-like blade with aleading end being connected to the front end of the bone screw and atrailing end being connected to the rear end of the bone screw. Theblade is further provided with a coaxial longitudinal aperture having alength extending between the leading end and the trailing end, and awidth. Further, the blade is coaxially and rotatably mounted on theshaft of the bone screw.

(7) United States Patent Application Publication Number 2010/0312245 toTipirneni et al.

United States Patent Application Publication Number2010/0312245—published to Tipirneni et al. on Dec. 9, 2010 in U.S. class606 and subclass 62—teaches a bone screw including a sleeve, a shaftreciprocally received within the sleeve, and a compressive device. Thebone screw may be extended—placing a fracture in tension—after insertioninto a bone, and then retained in place by a setscrew that is retainedby an intramedullary rod. The shaft of the bone screw has a blade threadthat allows the bone screw to be installed into a bone by tapping thebone screw with a hammer.

It is apparent that numerous innovations for osteosynthetic devices havebeen provided in the prior art, which are adapted to be used.Furthermore, even though these innovations may be suitable for thespecific individual purposes to which they address, nevertheless, theywould not be suitable for the purposes of the embodiments of the presentinvention as heretofore described, namely, an interchangeable orthopedicblade for more accurately placing in, without excessive damage to, abone when repairing a fracture in the bone by cooperating with aninterchangeable orthopedic plate, so as to provide absolute stablefixation by holding the fracture in its anatomic position and resistapplied forces while healing, to thereby provide a stable anatomicrestoration and eliminate a need for revision surgery due to failure offixation or malunion.

3. SUMMARY OF THE INVENTION

Thus, an object of the embodiments of the present invention is toprovide an interchangeable orthopedic blade for more accurately placingin, without excessive damage to, a bone when repairing a fracture in thebone so as to provide absolute stable fixation by holding the fracturein its anatomic position and resist applied forces while healing, tothereby provide a stable anatomic restoration and eliminate a need forrevision surgery due to failure of fixation or malunion, and forcooperating with an applicable interchangeable plate, which avoids thedisadvantages of the prior art.

Briefly stated, another object of the embodiments of the presentinvention is to provide an interchangeable orthopedic blade that moreaccurately places in, without excessive damage to, a bone when repairinga fracture in the bone so as to provide absolute stable fixation byholding the fracture in its anatomic position and resist applied forceswhile healing, to thereby provide a stable anatomic restoration andeliminate a need for revision surgery due to failure of fixation ormalunion, and further cooperating with an applicable interchangeableplate. The interchangeable orthopedic blade includes an internal portionand an external portion. The internal portion more accurately places theinterchangeable orthopedic blade in, without excessive damage to, thebone when repairing the fracture in the bone and ultimately provideabsolute stable fixation by the interchangeable orthopedic blade holdingthe fracture in its anatomic position and resisting applied forces whilehealing, to thereby provide a stable anatomic restoration and eliminatea need for revision surgery due to failure of fixation or malunion. Theinternal portion is received in the external portion and rotatesrelative to the external portion, but has the external portion movenon-rotatably axially with the internal portion into the bone as theinternal portion threads. In a first preferred embodiment, the internalportion is a screw with an externally threaded head. In a secondpreferred embodiment, the internal portion is an externally threaded setscrew.

The novel features considered characteristic of the embodiments of thepresent invention are set forth in the appended claims. The embodimentsof the present invention themselves, however, both as to theirconstruction and to their method of operation together with additionalobjects and advantages thereof will be best understood from thefollowing description of the embodiments of the present invention whenread and understood in connection with the accompanying figures of thedrawing.

4. BRIEF DESCRIPTION OF THE FIGURES OF THE DRAWING

The figures of the drawing are briefly described as follows:

FIG. 1 is a diagrammatic side elevational view of a common screw;

FIG. 2 is a diagrammatic side elevational view of the threads of acommon screw, which are defined by its major or outside and minor orroot diameters, pitch, lead, and number of threads;

FIG. 3 is a diagrammatic top plan view of the head drive types of thecommon screw;

FIG. 4 is a diagrammatic side elevational view of the biomechanics ofcannulated and noncannulated screws;

FIG. 5 is a diagrammatic top plan view of lag screw fixation thatproduces maximum interfragmentary compression when the screw is placedperpendicular to the fracture line;

FIG. 6 is a diagrammatic side elevational view showing lag screwfixation producing maximum interfragmentary compression when the screwis placed perpendicular to the fracture line;

FIG. 7 is a diagrammatic side elevational view showing lag screwfixation producing minimum interfragmentary compression when the screwis not placed perpendicular to the fracture line;

FIG. 8 is a diagrammatic side plan views of a T-lag screw compressing aclean fracture;

FIG. 9 is a diagrammatic side elevational view of a T-lag screwcompressing a jagged fracture;

FIG. 10 is a diagrammatic side elevational view of a locked plate screwfunctioning as a bolt;

FIG. 11 is a diagrammatic side elevational view of another locked platescrew functioning as an internal-external fixator;

FIG. 12 is a diagrammatic side elevational view illustrating the dynamiccompression principle;

FIG. 13 is diagrammatic side elevational view of the structure of alimited-contact dynamic compression plate;

FIG. 14A is a diagrammatic side elevational view illustrating that inthe dynamic compression plate, the area at the plate holes is less stiffthan the area between them so that during bending, the plate tends tobend only in the areas of the holes;

FIG. 14B is a diagrammatic side elevational view of the limited-contactdynamic compression plate having an even stiffness without the risk ofbuckling at the screw holes;

FIG. 15 is a diagrammatic side elevational view of the application ofthe drill guides depending on the proposed function of the screw througha neutral position and a compression position;

FIG. 16 is a diagrammatic elevational view of the 3.5 one-third tubularplate that is 1 mm thick and allows for limited stability so that thethin design allows for easy shaping and is primarily used on the lateralmalleolus and distal ulna, wherein the oval holes allow for limitedfracture compression with eccentric screw placement;

FIGS. 17A-17D are diagrammatic side elevational views of angled or bladeplates that are useful in repair of metaphyseal fractures of the femur,but the popularity has declined with the rise of sliding screw platesand locking plates, wherein proper insertion requires careful technique,with the blade inserted with consideration for 3 dimensions(varus/valgus blade angulation, anterior/posterior blade position, andflexion/extension rotation of blade plate);

FIGS. 18A and 18B are diagrammatic perspective views of reconstructionplates that are thicker than the tubular plates but not quite as thickas dynamic compression plates, and designed with deep notices betweenthe holes, and can be contoured in 3 planes to fit complex surfaces, asaround the pelvis and acetabulum, wherein reconstruction plates areprovided in straight and slightly thicker and stiffer precurved lengths,and wherein as with tubular plates, they have oval screw holes allowingpotential for limited compression;

FIGS. 19A and 19B are diagrammatic side elevational views illustratingthe tension-band principle;

FIG. 20 is diagrammatic side elevational view illustrating thetension-band principle at the femur;

FIG. 21 is a diagrammatic perspective view of an angled plate;

FIG. 22 is a diagrammatic perspective view of another type of angledplate;

FIG. 23 is a diagrammatic perspective view of the first embodiment ofthe interchangeable orthopedic blade of the embodiments of the presentinvention more accurately placing in, without excessive damage to, abone when repairing a fracture in the bone so as to provide absolutestable fixation by holding the fracture in its anatomic position andresist applied forces while healing, to thereby provide a stableanatomic restoration and eliminate a need for revision surgery due tofailure of fixation or malunion, and for cooperating with an applicableinterchangeable plate;

FIG. 24 is an enlarged diagrammatic perspective view of theinterchangeable orthopedic blade of the embodiments of the presentinvention identified by ARROW 24 in FIG. 23;

FIG. 25 is a reduced diagrammatic cross sectional view taken along LINE25-25 in FIG. 24;

FIG. 26 is a diagrammatic perspective view of the interchangeableorthopedic blade of the embodiments of the present invention cooperatingwith an applicable interchangeable plate identified by ARROW 26 in FIG.23;

FIG. 27 is a diagrammatic perspective view of the interchangeableorthopedic blade of the embodiments of the present invention cooperatingwith an applicable interchangeable plate identified by ARROW 27 in FIG.23;

FIG. 28 is an enlarged diagrammatic perspective view of the areagenerally enclosed by the dotted curve identified by ARROW 28 in FIG.26;

FIG. 29 is an enlarged diagrammatic perspective view of the areagenerally enclosed by the dotted curve identified by ARROW 29 in FIG.27;

FIG. 30 a diagrammatic perspective view of the second embodiment of theinterchangeable orthopedic blade of the embodiments of the presentinvention more accurately placing in, without excessive damage to, abone when repairing a fracture in the bone so as to provide absolutestable fixation by holding the fracture in its anatomic position andresist applied forces while healing, to thereby provide a stableanatomic restoration and eliminate a need for revision surgery due tofailure of fixation or malunion, and for further cooperating with anapplicable interchangeable plate;

FIG. 31 is a cross sectional view of the interchangeable orthopedicblade of the embodiments of the present invention taken along LINE 31-31in FIG. 30;

FIG. 32 is an exploded diagrammatic side elevational view of theinterchangeable orthopedic blade identified by ARROW 32 in FIG. 30; and

FIG. 33 is a cross sectional view of the interchangeable orthopedicblade of the embodiments of the present invention taken along LINE 33-33in FIG. 30.

5. LIST OF REFERENCE NUMERALS UTILIZED IN THE FIGURES OF THE DRAWING A.Introductory First Embodiment

-   30 interchangeable orthopedic blade of embodiments of present    invention for more accurately placing in, without excessive damage    to, bone 32 when repairing fracture 34 in bone 32 so as to provide    absolute stable fixation by holding fracture 34 in anatomic position    and resist applied forces while healing, to thereby provide stable    anatomic restoration and eliminate need for revision surgery due to    failure of fixation or malunion, and for further cooperating with    applicable interchangeable plate 40-   32 bone-   34 fracture of bone 32-   40 applicable interchangeable plate 40

B. Overall Configuration of First Embodiment of InterchangeableOrthopedic Blade 30

-   42 internal portion for more accurately placing interchangeable    orthopedic blade 30 in, without excessive damage to, bone 32 when    repairing fracture 34 in bone 32 and ultimately provide absolute    stable fixation by interchangeable orthopedic blade 30 holding    fracture 34 in anatomic position and resisting applied forces while    healing, to thereby provide stable anatomic restoration and    eliminate need for revision surgery due to failure of fixation or    malunion-   44 external portion

C. Specific Configuration of Internal Portion 42 and External Portion 44

(1) Internal Portion 42.

-   45 slender and elongated screw of internal portion 42-   46 proximal end of slender and elongated screw 45 of internal    portion 42-   48 distal end of slender and elongated screw 45 of internal portion    42-   50 external threads of slender and elongated screw 45 of internal    portion 42 for threadably engaging into bone 32-   52 tapered distal end of distal end 48 of slender and elongated    screw 45 of internal portion 42 for facilitating passage through    bone 32-   54 screw head of proximal end 46 of slender and elongated screw 45    of internal portion 42 for threadably engaging in applicable    interchangeable plate 40-   56 external threads of screw head 54 of proximal end 46 of slender    and elongated screw 45 of internal portion 42

(2) External Portion 44.

-   58 slender, elongated, and generally cylindrically shaped sleeve of    external portion 44-   60 proximal end of slender, elongated, and generally cylindrically    shaped sleeve 58 of external portion 44-   62 distal end of slender, elongated, and generally cylindrically    shaped sleeve 58 of external portion 44-   64 tapered and/or fluted distal end of distal end 62 of slender,    elongated, and generally cylindrically shaped sleeve 58 of external    portion 44 for facilitating passage through bone 32 during threading    of slender and elongated screw 45 of internal portion 42 into bone    32-   66 ring-like proximal end of proximal end 60 of slender, elongated,    and generally cylindrically shaped sleeve 58 of external portion 44-   72 at least a shoulder defining ring-like proximal end 66 of    proximal end 60 of slender, elongated, and generally cylindrically    shaped sleeve 58 of external portion 44-   74 at least one fin of external portion 44-   76 portion of at least one fin 74 of external portion 44-   78 at least one diverging fin extension of at least one fin 74 of    external portion 44

D. Method of Utilizing Interchangeable Orthopedic Blade 30 inCooperation with Applicable Interchangeable Plate 40

-   80 specifically configured through bore in applicable    interchangeable plate 40-   82 at least one tapered cutout of specifically configured through    bore 80 in applicable interchangeable plate 40-   84 threads in specifically configured through bore 80 in applicable    interchangeable plate 40

E. Introductory Second Embodiment

-   130 interchangeable orthopedic blade of embodiments of present    invention for more accurately placing in, without excessive damage    to, bone 132 when repairing fracture 134 in bone 132 so as to    provide absolute stable fixation by holding fracture 134 in anatomic    position and resist applied forces while healing, to thereby provide    stable anatomic restoration and eliminate need for revision surgery    due to failure of fixation or malunion, and for further cooperating    with applicable interchangeable plate 140-   132 bone-   134 fracture in bone 132-   140 applicable interchangeable plate

F. Overall Configuration of Second Embodiment of InterchangeableOrthopedic Blade 130

-   142 internal portion-   144 external portion

G. Specific Configuration of Internal Portion 142 and External Portion144

(1) Internal Portion 142.

-   144 a fastener of internal portion 142-   144 c externally threaded set screw of fastener 144 a of internal    portion 142

(2) External Portion 144.

-   158 slender, elongated, and generally cylindrically shaped sleeve of    external portion 144-   160 proximal end of slender, elongated, and generally cylindrically    shaped sleeve 158 of external portion 144-   162 distal end of slender, elongated, and generally cylindrically    shaped sleeve 158 of external portion 144-   164 tapered and/or fluted distal end of distal end 162 of slender,    elongated, and generally cylindrically shaped sleeve 158 of external    portion 144 for facilitating passage through bone 132-   166 ring-like proximal end of proximal end 160 of slender,    elongated, and generally cylindrically shaped sleeve 158 of external    portion 144-   172 shoulder of ring-like proximal end 166 of proximal end 160 of    slender, elongated, and generally cylindrically shaped sleeve 158 of    external portion 144-   174 at least one fin of external portion 144-   176 portion of at least one fin 174 of external portion 144-   178 at least one diverging fin extension of at least one fin 174 of    external portion 144-   180 specifically configured through bore in applicable    interchangeable plate 140-   182 at least one tapered cutout of specifically configured through    bore 180 in applicable interchangeable plate 140

H. Method of Utilizing Interchangeable Orthopedic Blade 130 inCooperation with Applicable Interchangeable Plate 140

-   184 internal threads in specifically configured through bore 180 in    applicable interchangeable plate 140

6. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A. IntroductoryFirst Embodiment

Referring now to FIG. 23, the interchangeable orthopedic blade of theembodiments of the present invention is shown generally at 30 for moreaccurately placing in, without excessive damage to, a bone 32 whenrepairing a fracture 34 in the bone 32 so as to provide absolute stablefixation by holding the fracture 34 in its anatomic position and resistapplied forces while healing, to thereby provide a stable anatomicrestoration and eliminate a need for revision surgery due to failure offixation or malunion, and for further cooperating with an applicableinterchangeable plate 40.

B. Overall Configuration of the First Embodiment of the InterchangeableOrthopedic Blade 30

The overall configuration of the first embodiment of the interchangeableorthopedic blade 30 can best be seen in FIG. 24, and as such, will bediscussed with reference thereto.

The interchangeable orthopedic blade 30 comprises an internal portion 42and an external portion 44.

The internal portion 42 is for more accurately placing theinterchangeable orthopedic blade 30 in, without excessive damage to, thebone 32 when repairing the fracture 34 in the bone 32 and ultimatelyprovide absolute stable fixation by the interchangeable orthopedic blade30 holding the fracture 34 in its anatomic position and resistingapplied forces while healing, to thereby provide a stable anatomicrestoration and eliminate a need for revision surgery due to failure offixation or malunion. The internal portion 42 is received in theexternal portion 44. The internal portion 42 rotates relative to theexternal portion 44, but has the external portion 44 move non-rotatablyaxially with the internal portion 42 into the bone 32 as the internalportion 42 threads.

C. Specific Configuration of the Internal Portion 42 and the ExternalPortion 44

The specific configuration of the internal portion 42 and the externalportion 44 can best be seen in FIGS. 24 and 25, and as such, will bediscussed with reference thereto.

(1) The Internal Portion 42.

The internal portion 42 is a slender and elongated screw 45.

The slender and elongated screw 45 of the internal portion 42 has aproximal end 46, a distal end 48, and external threads 50.

The external threads 50 of the slender and elongated screw 45 of theinternal portion 42 extend axially from the proximal end 46 of theslender and elongated screw 45 of the internal portion 42 to the distalend 48 of the slender and elongated screw 45 of the internal portion 42,and are for threadably engaging into the bone 32.

The distal end 48 of the slender and elongated screw 45 of the internalportion 42 is a tapered distal end 52. The tapered distal end 52 of thedistal end 48 of the slender and elongated screw 45 of the internalportion 42 is for facilitating passage through the bone 32.

The proximal end 46 of the slender and elongated screw 45 of theinternal portion 42 is a screw head 54. The screw head 54 of theproximal end 46 of the slender and elongated screw 45 of the internalportion 42 has external threads 56. The external threads 56 of the screwhead 54 of the proximal end 46 of the slender and elongated screw 45 ofthe internal portion 42 are for threadably engaging in the applicableinterchangeable plate 40.

(2) The External Portion 44.

The external portion 44 is a slender, elongated, and generallycylindrically shaped sleeve 58.

The slender, elongated, and generally cylindrically shaped sleeve 58 ofthe external portion 44 has a proximal end 60 and a distal end 62.

The distal end 62 of the slender, elongated, and generally cylindricallyshaped sleeve 58 of the external portion 44 is a tapered and/or fluteddistal end 64. The tapered and/or fluted distal end 64 of the distal end62 of the slender, elongated, and generally cylindrically shaped sleeve58 of the external portion 44 is for facilitating passage through thebone 32 during threading of the slender and elongated screw 45 of theinternal portion 42 into the bone 32.

The proximal end 60 of the slender, elongated, and generallycylindrically shaped sleeve 58 of the external portion 44 is a ring-likeproximal end 66.

The ring-like proximal end 66 of the proximal end 60 of the slender,elongated, and generally cylindrically shaped sleeve 58 of the externalportion 44 is defined at least by a shoulder 72.

The internal portion 42 sits axially in the external portion 44, withthe screw head 54 of the proximal end 46 of the slender and elongatedscrew 45 of the internal portion 42 threading coaxially in theapplicable interchangeable plate 40.

The external portion 44 further has at least one fin 74. The at leastone fin 74 of the external portion 44 extends axially from the taperedand/or fluted distal end 64 of the distal end 62 of the slender,elongated, and generally cylindrically shaped sleeve 58 of the externalportion 44 to past the ring-like proximal end 66 of the proximal end 60of the slender, elongated, and generally cylindrically shaped sleeve 58of the external portion 44 so as to be flush with the screw head 54 ofthe proximal end 46 of the slender and elongated screw 45 of theinternal portion 42.

That portion 76 of the at least one fin 74 of the external portion 44extending upwardly from the ring-like proximal end 66 of the proximalend 60 of the slender, elongated, and generally cylindrically shapedsleeve 58 of the external portion 44 to flush with the screw head 54 ofthe proximal end 46 of the slender and elongated screw 45 of theinternal portion 42 extends divergently upwardly so as to form at leastone diverging fin extension 78.

The at least one diverging fin extension 78 of the at least one fin 74of the external portion 44 is adjacent to the screw head 54 of theproximal end 46 of the slender and elongated screw 45 of the internalportion 42 and rests in at least one tapered cutout 82 of thespecifically configured through bore 80 in the applicableinterchangeable plate 40, respectively.

D. Method of Utilizing the Interchangeable Orthopedic Blade 30 inCooperation with the Applicable Interchangeable Plate 40

The method of utilizing the interchangeable orthopedic blade 30 can bestbe seen in FIGS. 26-29, and as such, will be discussed with referencethereto.

The method of utilizing the interchangeable orthopedic blade 30 incooperation with the applicable interchangeable plate 40 comprises thesteps of:

-   STEP 1: Dropping the external portion 44 through a specifically    configured through bore 80 in the applicable interchangeable plate    40 until the at least one diverging fin extension 78 of the at least    one fin 74 of the external portion 44 rests in at least one tapered    cutout 82 of the specifically configured through bore 80 in the    applicable interchangeable plate 40, respectively;-   STEP 2: Dropping the slender and elongated screw 45 of the internal    portion 42 through the specifically configured through bore in the    applicable interchangeable plate 40 and into the external portion    44; and-   STEP 3: Threading the external threads 56 of the screw head 54 of    the proximal end 46 of the slender and elongated screw 45 of the    internal portion 42 into internal threads 84 in the specifically    configured through bore 80 in the applicable interchangeable plate    40 until the screw head 54 of the proximal end 46 of the slender and    elongated screw 45 of the internal portion 42 bottoms out against    the ring-like proximal end 66 of the proximal end 60 of the slender,    elongated, and generally cylindrically shaped sleeve 58 of the    external portion 44, to thereby lock the interchangeable orthopedic    blade 30 in place on the applicable interchangeable plate 40.

E. Introductory Second Embodiment

Referring now to FIG. 30, the interchangeable orthopedic blade of theembodiments of the present invention is shown generally at 130 for moreaccurately placing in, without excessive damage to, a bone 132 whenrepairing a fracture 134 in the bone 132 so as to provide absolutestable fixation by holding the fracture 134 in its anatomic position andresist applied forces while healing, to thereby provide a stableanatomic restoration and eliminate a need for revision surgery due tofailure of fixation or malunion, and for further cooperating with anapplicable interchangeable plate 140.

F. Overall Configuration of the Second Embodiment of the InterchangeableOrthopedic Blade 130

The overall configuration of the second embodiment of theinterchangeable orthopedic blade 130 can best be seen in FIG. 31, and assuch, will be discussed with reference thereto.

The interchangeable orthopedic blade 130 comprises an internal portion142 and an external portion 144.

The internal portion 142 is received in the external portion 144. Theinternal portion 142 rotates relative to the external portion 144, andthe external portion 144 moves non-rotatably axially into the bone 132.

G. Specific Configuration of the Internal Portion 142 and the ExternalPortion 144

The specific configuration of the internal portion 142 and the externalportion 144 can best be seen in FIGS. 32 and 33, and as such, will bediscussed with reference thereto.

(1) The Internal Portion 142.

The internal portion 142 is a fastener 144 a. The fastener 144 a of theinternal portion 142 is an externally threaded set screw 144 c. Theexternally threaded set screw 144 c of the fastener 144 a of theinternal portion 142 threads into the applicable interchangeable plate140 locking the external portion 144 from backing out.

(2) The External Portion 144.

The external portion 144 is a slender, elongated, and generallycylindrically shaped sleeve 158.

The slender, elongated, and generally cylindrically shaped sleeve 158 ofthe external portion 144 has a proximal end 160 and a distal end 162.

The distal end 162 of the slender, elongated, and generallycylindrically shaped sleeve 158 of the external portion 144 is a taperedand/or fluted distal end 164. The tapered and/or fluted distal end 164of the distal end 162 of the slender, elongated, and generallycylindrically shaped sleeve 158 of the external portion 144 is forfacilitating passage through the bone 132.

The proximal end 160 of the slender, elongated, and generallycylindrically shaped sleeve 158 of the external portion 144 is aring-like proximal end 166.

The ring-like proximal end 166 of the proximal end 160 of the slender,elongated, and generally cylindrically shaped sleeve 158 of the externalportion 144 is defined at least by a shoulder 172.

The internal portion 142 sits axially in the external portion 144, withthe externally threaded set screw 144 c of the fastener 144 a of theinternal portion 142 threading coaxially into the applicableinterchangeable plate 140.

The external portion 144 further has at least one fin 174. The at leastone fin 174 of the external portion 144 extends axially from the taperedand/or fluted distal end 164 of the distal end 162 of the slender,elongated, and generally cylindrically shaped sleeve 158 of the externalportion 144 to past the ring-like proximal end 166 of the proximal end160 of the slender, elongated, and generally cylindrically shaped sleeve158 of the external portion 144 so as to be flush with the externallythreaded set screw 144 c of the fastener 144 a of the internal portion142.

That portion 176 of the at least one fin 174 of the external portion 144extending upwardly from the ring-like proximal end 166 of the proximalend 160 of the slender, elongated, and generally cylindrically shapedsleeve 158 of the external portion 144 to flush with the externallythreaded set screw 144 c of the fastener 144 a of the internal portion142 extends divergently upwardly so as to form at least one divergingfin extension 178.

The at least one diverging fin extension 178 of the at least one fin 174of the external portion 144 is adjacent to the externally threaded setscrew 144 c of the fastener 144 a of the internal portion 142 and restsin at least one tapered cutout 182 of the specifically configuredthrough bore 180 in the applicable interchangeable plate 140,respectively.

The externally threaded set screw 144 c of the fastener 144 a of theinternal portion 142 threads coaxially into the applicableinterchangeable plate 140, rests against the at least a shoulder 172 ofthe ring-like proximal end 166 of the proximal end 160 of the slender,elongated, and generally cylindrically shaped sleeve 158 of the externalportion 144, and is adjacent to the at least one diverging fin extension178 of the at least one fin 174 of the external portion 144.

H. Method of Utilizing the Interchangeable Orthopedic Blade 130 inCooperation with the Applicable Interchangeable Plate 140

The method of utilizing the interchangeable orthopedic blade 130 canbest be seen in FIG. 33, and as such, will be discussed with referencethereto.

The method of utilizing the interchangeable orthopedic blade 130 incooperation with the applicable interchangeable plate 140 comprises thesteps of:

-   STEP 1: Dropping the external portion 144 through the specifically    configured through bore 180 in the applicable interchangeable plate    140 until the at least one diverging fin extension 178 of the at    least one fin 174 of the external portion 144 rests in at least one    tapered cutout 182 of the specifically configured through bore 180    in the applicable interchangeable plate 140, respectively;-   STEP 2: Dropping the externally threaded set screw 144 c of the    fastener 144 a of the internal portion 142 into the specifically    configured through bore 180 in the applicable interchangeable plate    140; and-   STEP 3: Threading the externally threaded set screw 144 c of the    fastener 144 a of the internal portion 142 into internal threads 184    in the specifically configured through bore 180 in the applicable    interchangeable plate 140 until the externally threaded set screw    144 c of the fastener 144 a of the internal portion 142 bottoms out    against the ring-like proximal end 166 of the proximal end 160 of    the slender, elongated, and generally cylindrically shaped sleeve    158 of the external portion 144, to thereby lock the interchangeable    orthopedic blade 130 in place on the applicable interchangeable    plate 140.

I. Impressions

It will be understood that each of the elements described above or twoor more together may also find a useful application in other types ofconstructions differing from the types described above.

While the embodiments of the present invention have been illustrated anddescribed as embodied in an interchangeable orthopedic blade for moreaccurately placing in, without excessive damage to, a bone whenrepairing a fracture in the bone by cooperating with an interchangeableorthopedic plate, so as to provide absolute stable fixation by holdingthe fracture in its anatomic position and resist applied forces whilehealing, to thereby provide a stable anatomic restoration and eliminatea need for revision surgery due to failure of fixation or malunion,nevertheless, they are not limited to the details shown, since it willbe understood that various omissions, modifications, substitutions, andchanges in the forms and details of the embodiments of the presentinvention illustrated and their operation can be made by those skilledin the art without departing in any way from the spirit of theembodiments of the present invention.

Without further analysis, the foregoing will so fully reveal the gist ofthe embodiments of the present invention that others can by applyingcurrent knowledge readily adapt them for various applications withoutomitting features that from the standpoint of prior art fairlyconstitute characteristics of the generic or specific aspects of theembodiments of the present invention.

The invention claimed is:
 1. An interchangeable orthopedic blade formore accurately placing in, without excessive damage to, a bone whenrepairing a fracture in the bone so as to provide absolute stablefixation by holding the fracture in its anatomic position and resistapplied forces while healing, to thereby provide a stable anatomicrestoration and eliminate a need for revision surgery due to failure offixation or malunion, and for further cooperating with an applicableinterchangeable plate, said interchangeable orthopedic blade comprising:a) an internal portion; and b) an external portion; wherein saidinternal portion is for more accurately placing said interchangeableorthopedic blade in, without excessive damage to, the bone whenrepairing the fracture in the bone and ultimately provide absolutestable fixation by said interchangeable orthopedic blade holding thefracture in its anatomic position and resisting applied forces whilehealing, to thereby provide a stable anatomic restoration and eliminatea need for revision surgery due to failure of fixation or malunion;wherein said internal portion is received in said external portion; andwherein said internal portion rotates relative to said external portion,but has said external portion move non-rotatably axially with saidinternal portion into the bone as said internal portion threads.
 2. Theinterchangeable orthopedic blade of claim 1, wherein said internalportion is a slender and elongated screw.
 3. The interchangeableorthopedic blade of claim 2, wherein said slender and elongated screw ofsaid internal portion has: a) a proximal end; b) a distal end; and c)external threads.
 4. The interchangeable orthopedic blade of claim 3,wherein said external threads of said slender and elongated screw ofsaid internal portion extend axially from said proximal end of saidslender and elongated screw of said internal portion to said distal endof said slender and elongated screw of said internal portion; andwherein said external threads of said slender and elongated screw ofsaid internal portion are for threadably engaging into the bone.
 5. Theinterchangeable orthopedic blade of claim 3, wherein said distal end ofsaid slender and elongated screw of said internal portion is a tapereddistal end; and wherein said tapered distal end of said distal end ofsaid slender and elongated screw of said internal portion is forfacilitating passage through the bone.
 6. The interchangeable orthopedicblade of claim 3, wherein said proximal end of said slender andelongated screw of said internal portion is a screw head; wherein saidscrew head of said proximal end of said slender and elongated screw ofsaid internal portion has external threads; and wherein said externalthreads of said screw head of said proximal end of said slender andelongated screw of said internal portion are for threadably engaging insaid applicable interchangeable plate.
 7. The interchangeable orthopedicblade of claim 6, wherein said external portion is a slender, elongated,and generally cylindrically shaped sleeve.
 8. The interchangeableorthopedic blade of claim 7, wherein said slender, elongated, andgenerally cylindrically shaped sleeve of said external portion has: a) aproximal end; and b) a distal end.
 9. The interchangeable orthopedicblade of claim 8, wherein said distal end of said slender, elongated,and generally cylindrically shaped sleeve of said external portion is atleast one of a tapered distal end and a fluted distal end; and whereinsaid at least one of said tapered distal end and said fluted distal endof said distal end of said slender, elongated, and generallycylindrically shaped sleeve of said external portion is for facilitatingpassage through the bone during threading of said slender and elongatedscrew of said internal portion into the bone.
 10. The interchangeableorthopedic blade of claim 9, wherein said proximal end of said slender,elongated, and generally cylindrically shaped sleeve of said externalportion is a ring-like proximal end.
 11. The interchangeable orthopedicblade of claim 10, wherein said ring-like proximal end of said proximalend of said slender, elongated, and generally cylindrically shapedsleeve of said external portion is defined at least by a shoulder. 12.The interchangeable orthopedic blade of claim 11, wherein said internalportion sits axially in said external portion.
 13. The interchangeableorthopedic blade of claim 10, wherein said external portion has at leastone fin.
 14. The interchangeable orthopedic blade of claim 13, whereinsaid at least one fin of said external portion extends axially from saidat least one of said tapered distal end and said fluted distal end ofsaid distal end of said slender, elongated, and generally cylindricallyshaped sleeve of said external portion to past said ring-like proximalend of said proximal end of said slender, elongated, and generallycylindrically shaped sleeve of said external portion so as to be flushwith said screw head of said proximal end of said slender and elongatedscrew of said internal portion.
 15. The interchangeable orthopedic bladeof claim 6, wherein that portion of said at least one fin of saidexternal portion extends upwardly from said ring-like proximal end ofsaid proximal end of said slender, elongated, and generallycylindrically shaped sleeve of said external portion to flush with saidscrew head of said proximal end of said slender and elongated screw ofsaid internal portion extends divergently upwardly so as to form atleast one diverging fin extension.
 16. The interchangeable orthopedicblade of claim 15, wherein said at least one diverging fin extension ofsaid at least one fin of said external portion is adjacent to said screwhead of said proximal end of said slender and elongated screw of saidinternal portion; and wherein said at least one diverging fin extensionof said at least one fin of said external portion rests in at least onetapered cutout of the specifically configured through bore in theapplicable interchangeable plate, respectively.
 17. The interchangeableorthopedic blade of claim 13, wherein said internal portion is anexternally threaded set screw.
 18. The interchangeable orthopedic bladeof claim 17, wherein said externally threaded set screw of said internalportion threads into a specifically configured through bore in saidapplicable interchangeable plate locking said external portion frombacking out.
 19. A method of utilizing an interchangeable orthopedicblade in cooperation with an applicable interchangeable plate, whereinthe interchangeable orthopedic blade includes: a) an external portionhaving: i) at least one fin with at least one diverging fin extension;and ii) a slender, elongated, and generally cylindrically shaped sleevewith a proximal end that is a ring-like proximal end; b) an internalportion having: i) a slender and elongated screw with a proximal endbeing a screw head with external threads; wherein the applicableinterchangeable plate includes: a) a specifically configured throughbore having: i) at least one tapered cutout; and ii) internal threads,wherein said method comprising the steps of: a) dropping the externalportion through the specifically configured through bore in theapplicable interchangeable plate until the at least one diverging finextension of the at least one fin of the external portion rests in theat least one tapered cutout of the specifically configured through borein the applicable interchangeable plate, respectively; b) dropping theslender and elongated screw of the internal portion through thespecifically configured through bore in the applicable interchangeableplate and into the external portion; and c) threading the externalthreads of the screw head of the proximal end of the slender andelongated screw of the internal portion into the in the specificallyconfigured through bore in the applicable interchangeable plate untilthe screw head of the proximal end of the slender and elongated screw ofthe internal portion bottoms out against the ring-like proximal end ofproximal end of the slender, elongated, and generally cylindricallyshaped sleeve of the external portion, to thereby lock theinterchangeable orthopedic blade in place on the applicableinterchangeable plate.
 20. A method of utilizing an interchangeableorthopedic blade in cooperation with an applicable interchangeableplate, wherein the interchangeable orthopedic blade includes: a) anexternal portion having: i) at least one fin with at least one divergingfin extension; and ii) a slender, elongated, and generally cylindricallyshaped sleeve with a proximal end that is a ring-like proximal end; b)an internal portion having: i) an externally threaded set screw whereinthe applicable interchangeable plate includes: a) a specificallyconfigured through bore having: i) at least one tapered cutout; and ii)internal threads, wherein said method comprising the steps of: a)dropping the external portion through the specifically configuredthrough bore in the applicable interchangeable plate until the at leastone diverging fin extension of the at least one fin of the externalportion rests in at least one tapered cutout of the specificallyconfigured through bore in the applicable interchangeable plate,respectively; b) dropping the externally threaded set screw of theinternal portion into the specifically configured through bore in theapplicable interchangeable plate; and c) threading the externallythreaded set screw of the internal portion into the internal threads inthe specifically configured through bore in the applicableinterchangeable plate until the externally threaded set screw of theinternal portion bottoms out against the ring-like proximal end of theproximal end of the slender, elongated, and generally cylindricallyshaped sleeve of the external portion, to thereby lock theinterchangeable orthopedic blade in place on the applicableinterchangeable plate.